Did you ever stop to reflect on your wins? Did you collect the data somewhere? If not, do it and make sure you have it stored away somewhere you can access it even if you leave the company.
I'm applying for jobs and if there's one thing I wish I would have done it's exactly that. Being able to add data to your resume or answer in interviews with real numbers of how you increase from X to Y is golden. A lot of recruiters want to see real and tangible outcomes rather than generic statements that just about anyone can make whether they are real or not.
If there's anything I wish I could do as far as looking through old data from my system it's having a look at what I've jotted down in self-assessment as well as pulling a few reports on what I accomplished.
If you're still there but don't know for how long. Take a moment to document these things while you still have access to them, it'll make life easier on the other side.